Denture cushion composition and method for making the same



April 21, 1959 Row 2,883,353

M. LASE DENTURE CUSHION COMPOSITION AND METHOD FOR MAKING THE SAME. Filed April 13, 1955 FIG.

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ATTORNEY United States Patent DENTURE CUSHION COMPOSITION AND METHOD FOR MAKING THE SAME Max Laserow, Malmo, Sweden, assignor to Abraham Lieberson, Philadelphia, Pa.

Application April 13, 1955, Serial No. 501,172 3 Claims. (Cl. 260-23) The present invention relates to a cushion composition for dentures, and more particularly, to an odorless, tasteless, insoluble composition of matter which will remain soft within the human mouth for extended periods of time; and to a method for forming such composition.

After oral surgery, changes in dentures, or other therapeutic measures in the mouth, it has been found that the patients oral tissues, such as the gums and palate, are tender and that any slight irritation thereof proves to be most painful. In particular, it has been found that the insertion of a denture, such as a partial denture, subsequent to oral surgery proves most painful. For this reason, in many instances, a patient will refuse to wear a denture after surgical treatment, or change in prosthetic devices, and thus deprive himself of the aid in mastication furnished thereby.

To alleviate this problem, attempts have been made to develop so-called treatment reline cushions which cling to the surface of a denture juxtaposed to the wearers gingival, alveolar and/or palatal tissues. These cushions have comprised methyl methacrylate polymers which have been retained on the denture, while the denture is worn.

However, these prior cushions have to a large extent proven unsatisfactory for a variety of reasons. Thus, in many instances the cushion material possesses an odor and/ or taste, unpleasant to the wearer; or comprises materials which chemically irritate the sensitive tissues of the wearer. Furthermore, prior materials have failed to cling to the wearers denture and have become dissociated therefrom after a relatively short duration of time.

,Most seriously, no prior cushion that has heretofore been developed has remained soft when worn for more than a fewweeks or months at the most. All prior cushions have the disadvantage of gradually hardening within the wearers mouth, and ultimately being converted into a form which will irritate the wearer.

It is an" object of the present invention to provide a superior denture cushion composition.

A further object of the present invention is the provision of a denture cushion composition that will remain soft indefinitely, when worn within the human mouth.

Another object of the present invention is the provision of a denture cushion composition that will cling to a denture.

A still further object of the present invention is the provision of a denture cushion composition that is odorless and tasteless, and will not chemically irritate sensitive oral tissues.

These and other objects of the present invention are accomplished by the composition of my invention in which a relatively high molecular weight diester of a dibasic organic acid, preferably a dibasic organic acid which forms a monomeric anhydride, such as the diesters of phthalic, malic, succinic or glutaric acids, or the diester of a dibasic organic acid which forms a cyclic ketone on heating with acetic anhydride, such as adipic, pimelic, suberic or like acids, which diester is derived from alcohols having from about six to ten carbon atoms,

Patented Apr. 21, 1959 and preferably about eight carbon atoms; e.g., such as dioctyl adipate, or dioctyl phthalate, is combined preferably in the presence of a small amount of castor oil or related vegetable oil, with a trace amount of aniline, and a significant amount of a copolymer of vinyl chloride and vinyl acetate, and a trace amount of an odor-free petroleumhydrocarbon oil.

For the purpose of illustrating the invention there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

Figure 1 is a perspective view of a denture comprising a plate of the present invention.

Figure 2 is a section on line 22 of Figure 1.

Referring to the drawings, the denture of the present invention is designated by the numeral 8 and comprises a plurality of teeth 10 made of porcelain, plastic or the like and disposed in the denture to articulate with the teeth of the lower jaw of the wearer. The teeth 10 are anchored in a plate 12, which may be formed from any one of a large variety of compositions useful for that purpose.

A denture cushion 14 is positioned on the upper surface of the denture 8 of the present invention, said denture cushion 14 being formed of the denture composition of the present invention. Said denture cushion 14 is odorless and tasteless, and will not chemically irritate sensitive oral tissues. It will remain soft indefinitely, when worn within the mouth, and will not become dissociated from the plate composition 12.

The concentrations in the composition of the diester and the vinyl copolymer should be preferably a major weight percentage of the diester, such as about 50 to 70 weight percent of the diester, and about 30 to 50 weight percent of the copolymer. The concentration of aniline should be of the order of a few thousandths of a percent or less, such as about five ten-thousandths to three thousandths of a percent, and the concentration of hydrocarbon oil to between about 0.05 and 0.12 weight percent. Castor oil, when present, should be limited to a concentration of not more than about 10 weight percent, and preferably should be well below this figure.

Of the diesters that have been tested, dioctyl adipate possesses the most beneficial attributes for the composition of the present invention, and is to be preferred.

The preferred vinyl copolymer resin is the so-called Vinylite resin VYNS3, marketed by the Bakelite Co., a division of Union Carbide International Corp., New York, NY. This polymer is prepared by mixing a major weight percentage of vinyl chloride and a minor weight percentage of vinyl acetate together, and copolymerising the mixture.

The method of the present invention comprises combining the diester of the polybasic acid, preferably with a minor amount of castor oil or related vegetable oil with aniline, such as /2 gram of aniline to 25 liters of diester, with vigorous stirring and then raising the temperature of the diester and aniline mixture to an elevated temperature below the boiling point of water, such as to a temperature of C. to C. with stirring.

The vinyl copolymer is mixed at room temperature, e.g., about 20 C., with a minor fraction of the aforesaid mixture. Thus, the entire vinyl copolymer component may be mixed with one-fifth its weight of the aforesaid aniline and diester mixture. The remainder of the aniline and diester mixture may then be warmed to about 65 C. to 75 C. and then added to the vinyl copolymer and the resultant mixture stirred vigorously for an extended period, such as five or so minutes.

The mineral oil, which should be a pharmaceutical grade colorless mineral oil is then added to the mixture,

and the stirring continued for an additional period of time, such as an additional two minutes.

The denture cushion composition of the present invention is odorless and tasteless and will remain soft within the mouth, as when on the back surface of a partial denture, indefinitely or substantially indefinitely.

Example 250 parts by weight of Plasticol II, a commercial homogeneous dioctyl adipate and castor oil mixture consisting of 98-99.5 weight percent of dioctyl adipate and the remainder of castor oil were thoroughly mixed at room temperature with 250 parts by weight of Plasticol I, a commercial homogeneous dioctyl adipate and castor oil mixture consisting of 90 weight percent of dioctyl adipate and weight percent of castor oil, and 200 parts by weight of pure dioctyl adipate. Plasticol II and Plasticol I may be obtained from C. V. Boysen & Co., Malmo, Sweden.

To each 25 liters of this mixture, V2 gram of aniline was added and the temperature was then raised to 77 C. with vigorous stirring.

The mixture was then cooled to room temperature and 100 parts by weight thereof was combined at room temperature with 500 parts by weight of a particulated Vinylite resin, namely a copolymer of vinyl chloride and vinyl acetate designated VYNS-3, marketed by the Bakelite Co., a division of Union Carbide International Corp., New York, NY.

The remaining 600 parts by weight of the dioctyl adipate, castor oil and aniline mixture was warmed to 70 C. and when so-warmed was added to the 600 parts by weight of the vinyl chloride and vinyl acetate copolymer, dioctyl adipate, castor oil and aniline mixture.

The resultant mixture of 1200 parts by weight was stirred vigorously for five minutes. Then, about 0.8-0.9 part by weight of an odor-free pharmaceutical-grade mineral oil was added to the mixture, and the combined mixture stirred for an additional two minutes to produce the superior denture cushion of the present invention.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

I claim:

1. A denture cushion which will cling to a denture and will remain soft, odorless, and tasteless when worn in the human month, said denture cushion consisting essentially of about 50 to 70 weight percent dioctyl adipate, 30 to 50 weight percent of a copolymer of a major weight percentage of vinyl chloride and a minor weight percentage of vinyl acetate, about 0.0005 to 0.003 weight percent of 4 aniline, about 0.05 to 0.12 weight percent of petroleum hydrocarbon oil and containing castor oil, said castor oil being present in a weight percentage of not more than about 10 weight percent of castor oil.

2. A method for forming a denture cushion composition which is odorless, tasteless and soft when worn in the human mouth which comprises mixing fifty to seventy parts by weight of dioctyl adipate with 0.0005 to 0.003 parts by weight of aniline, and heating said mixture to a temperature of between 75 to 80 C., cooling said mixture to room temperature, mixing said mixture with 30 to 50 parts by weight of a copolymer of a major weight percentage of vinyl chloride and a minor weight percentage of vinyl acetate, and adding about 0.05 to 0.12 parts by weight of a petroleum hydrocarbon oil thereto.

3. A method for forming a denture cushion composition which is odorless, tasteless and soft when worn in the human mouth which comprises mixing 50 to parts by weight of dioctyl adipate with 0.0005 to 0.003 parts by weight of aniline, and heating said mixture to a temperature of between to C., cooling said mixture to room temperature, mixing a portion of a major weight percentage of said mixture'with 30 to 50 parts by weight of a copolymer of vinyl chloride and a minor weight percentage of vinyl acetate, warming the remaining portion of said first mixture to 65 to 75 C., and adding such warmed mixture to the mixture containing the copolymer, and adding about 0.05 to 0.12 parts by weight of a petroleum hydrocarbon oil thereto.

References Cited in the file of this patent UNITED STATES PATENTS 1,990,903 Groff Feb. 12, 1935 2,013,941 Young et al Sept. 10, 1935 2,341,593 Burkhardt et a1 Feb. 15, 1944 2,450,435 McGillicuddy Oct. 5. 1948 2,487,254 Mahoney Nov. 8, 1949 2,528,507 Foye Nov. 7, 1950 2,711,999 Brandner et al June 28, 1955 FOREIGN PATENTS 558,470 Great Britain Jan. 6, 1944 OTHER REFERENCES Tylman et al.: Acrylics and Other Dental Resins, pages 46, 55-57, 61-63. J. B. Lippincott (1946).

Zimmerman et al.: Compounding of Polyvinyl Chld ride, pages 311-317: Rubber Age, vol. 68, No. 3, (December 1950).

Clark et al.: Compounding Plastisols for Specific Applications, Rubber Age, pages 343-349, vol. 72, No. 3 (December 1952). 

1. A DENTURE CUSHION WHICH WILL CLING TO A DENTURE AND WILL REMAIN SOFT, ODORLESS, AND TASTELESS WHEN WORN IN THE HUMAN MOUTH, SAID DENTURE CUSHION CONSISTING ESSENTIALLY OF ABOUT 50 TO 70 WEIGHT PERCENT DIOCTYL ADIPATE, 30 TO 50 WEIGHT PERCENT OF COPOLYMER OF A MAJOR WEIGHT PERCENTAGE OF VINYL CHLORIDE AND A MINOR WEIGHT PERCENTAGE OF VINYL ACETATE, ABOUT 0.0005 TO 0.003 WEIGHT PERCENT OF ANILINE, ABOUT 0.05 TO 0.12 WEIGHT PERCENT OF PETROLEUM HYDROCARBON OIL AND CONTAINING CASTOR OIL, SAID CASTOR OIL BEING PRESENT IN A WEIGHT PERCENTAGE OF NOT MORE THAN ABOUT 10 WEIGHT PERCENT OF CASTOR OIL. 